With the need for efficiency in representing cochlear hair cells, the use of an Infinite Impulse Response (IIR) resonator digital filter is preferred over its counterpart, the Finite Impulse Response (FIR) filter. Unlike an FIR filter, an IIR filter provides for computational efficiency and meaningful immediate output following a one cycle initialization, i.e., no staging delays, when given an input.
U.S. Pat. No. 5,432,723, entitled “Parallel Infinite Impulse Response (IIR) Filter with Low Quantization Effects and Method Therefor,” discloses a parallel IIR filter that features a multiplier and a number of biquad filters. While the present invention utilizes multipliers, it does not use biquad filters but uses other components not disclosed by Chen et al. in a way that is distinguishable from the device taught in U.S. Pat. No. 5,432,723. U.S. Pat. No. 5,432,723 is hereby incorporated by reference into the specification of the present invention.
U.S. Pat. No. 6,009,445, entitled “Reconfigurable Infinite Impulse Response (IIR) Digital Filter,” discloses an IIR filter that uses adders and a number of shift registers. While the present invention utilizes an adder, it also uses other components not disclosed by Tsyrganovich in a way that is distinguishable from the device taught in U.S. Pat. No. 6,009,445. U.S. Pat. No. 6,009,445 is hereby incorporated by reference into the specification of the present invention.